Answer:
$4080
Step-by-step explanation:
We have the amount she will pay back, but first, we need to find the Interest accrued.
Simple Interest is given as:

where P = principal
R = rate
T = time taken (in years)
Therefore, the interest on $3,000 at 9% simple interest for 4 years is:

I = $1080
Therefore, the amount she will pay back is:
$3000 + $1080 = $4080
Before you can add or subtract fractions with different denominators.you first have to find common denominators. subtract the numerators and reduce fraction.
Adding fractions make sure numbers are same add the numerators and put it over the denominator,simplify the fraction if needed
Yes D is the correct option !
if you want to know how , comment, or you are good to go !